Flexible stay-bolt connection for boilers.



B. E. D. STAFFORD. FLEXIBLE STAY BOLT CONNECHON FOR BOLLERS.

Patented Dec. 26, 1916.

S E 5 M. .N

BENJAMIN E. D. STAFFORD, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOB, TO FLANNERY FLEXIBLE STAY-BOLT CONNECTION FOR BOILERS.

Specification of Letters Patent.

Patented Dec. 26, 1916.

Application filed November 6, 1915. Serial No. 69,052.

To all whom it may concern:

Be it known that I, BENJAMIN E. D. STAFFORD, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Flexible Stay-Bolt Connections for Boilers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in flexible stay bolt connection for boilers, and is designed as an improvement on the construction disclosed in the Tate Patent No. 753,329, granted March 1, 1904.

In the Tate stay bolt, the sleeve or bushing carrying the head of the bolt is screwed directly into the roof sheet of the boiler. In many instances the stay bolt is not at right angles to the roof sheet, and as the axis of the sleeve should be as nearly as possible coincident with the axis of the bolt, it follows that in all instances where the sleeve is at an angle other than a right angle to the roof sheet, the threaded connection between the sleeve and roof sheet is weakened.

The object of this invention is to provide means whereby the sleeve may be firmly secured to the roof plate irrespective of the angle of the latter to the stay bolt, and it consists in a steel bushing welded to the roof sheet around the bolt opening therein and a sleeve screwed into the bushing, the axis of the sleeve being coincident with the axis of the bushing.

In the accompanying drawing, Figure 1 is a View in section showing my improvement applied to a roof plate, and Fig. 2' is a view of the bushing.

1 represents the roof plate or sheet of a locomotive boiler provided with an opening 2 for each stay bolt, the wall of each of said openings being parallel or approximately parallel with the long axis of the bolt passing through the same. The plate 1 is counterbored on its outer surface around said opening to receive and form a seat for the bushing 3, which is preferably made of drop forged or pressed steel and is conical in shape, the large or base end of the bushing being machined off to make a close fit with large end of the bushing to conform to the angle of stay bolt installation so that when seated on the sheet 1, its axis will be coincident with the axis of the bolt to be used therein as illustrated in Fig. 1.

The outer or smaller end of the bushing is provided with a threaded opening to engage the threaded end of the sleeve 5, which may be the ordinary Tate stay bolt sleeve. This sleeve is provided with an internal curved seat 6 to receive and support the head 7 of the bolt 8, the latter passing downwardly through the sleeve, bushing and space between the outer and inner sheets, and is screwed to the latter, 1, in the usual and well known manner. I have shown the head 7 of the bolt 8 secured to the latter by screw threads, but this is immaterial, as it may be an integral part of the bolt and may be spherical or partly spherical as desired or circumstances may require.

In assembling the parts the bushings are first milled, if necessary to conform to the angle of stay bolt installation and are the-n properly placed with relation to the bolt openings in the outer plate, after which the welding composition or filler is applied, as at 9, between the bushing and the shoulder 10 formed by counterboring the roof plate, after which the weld is effected by the oxyacetylene welding method, or by electrically welding the parts. The welding fuses the metals so that the union between the plate and sleeve is of a homogeneous character thereby securing all of the advantages of a bushing integral with the plate.

When the bushing is set its axis is coincident with the long axis of the sleeve 5, hence the threaded end of the sleeve has a firm and solid threaded connection with the end of the bushing at right angles to the sleeve which insures a tighter and more solid connection than can be effected between the sleeve and roof plate.

By simply milling 01f the inner end of the bushing the latter can 'be so set as to bring the long axis of the bolt at any desired angle to the roof plate, and. in each and every instance the long axis of the sleeve will be coincident with the long axis of'the bushing.

The head 7 of the bolt rests within the sleeve on the curved seat 6 of the latter in the usual and well known manner, and is covered and protected by the removable cap 11.

By counterboring the face of the roof plate, a shoulder or abutment 10 is formed which materially assists the welded joint in taking the lateral stresses, and I am also enabled to use a much smaller opening in the plate 1 for the passage of the bolt, thus conserving the strength of the plate and at the same time "forming a solid and substantial base for the bushing which is sufficient to withstand the hammer blows in testing the bolt, and in riveting up the inner end of the latter to the inner sheet of the boiler.

It is evident that many slight changes might be resorted to in the relative arrangement of parts shown and described without departing from the spirit and scope of my invention. Hence I would have it. understood that I do not wish to confine myself to the exact construction and arrangement of parts shown and described except as defined by the scope of the appended claims,

Having fully described my invention what I claim as new and desire to secure by Letters-Patent, is:

1. In stay bolt connection for boilers, the combination of a boiler plate having an opening for the passage of a bolt, a bushing welded to the outer face of the plate around the opening therein, and a sleeve having a threaded connection with the outer end of the bushing, the said sleeve having a seat for the head of the stay bolt.

2. In stay 'bolt connection for boilers, the combination of a boiler plate having an opening for the passage of a bolt, and a counterbore around said opening, a bushing welded within the counterbore and around the bolt opening in the plate and a sleeve having a threaded connection with the outer end of the bushing, the said sleeve having a seat for the outer end of the stay bolt, and a cap for closing the outer end of the sleeve.

In testimony whereof, Ihave signed this specification in the presence of two subscribing witnesses.

BENJAMIN E. D. STAFFORD;

Witnesses:

EDWIN SLRYQE', F. H. ALLISON.

co ies of this patent 'ifiay be obtained for five cents each, By addressing the commissioner or Patents Washington, D. 0. 

